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Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by carnage

Is the BQ-CC55 supposed to charge faster than the BQ-CC17? I bought a 8 pk of AA Eneloops, they all read 1.32 volts. I put 4 in the BQ-CC17 and 4 in the BQ-CC55 the BQ-CC17 finish about half hour before the BQ-CC55. Is this normal?

From my experience, no this is not at all normal.
All of my 1900 mAh LSD AA battery 4-pack kits when new were only about 67% full, give or take 1% or 2% and they all had initial no load voltages ~ 1.32 volts.

When charging four AA batteries, the BQ-CC55 uses a 750 mA charge rate.
The BQ-CC17 always uses a 300 mA charge rate for AA batteries all of the time, whether you're charging one, two, three or four batteries. This means that if all eight batteries have similar initial precharged capacity, the BQ-CC55 batteries should finish much sooner.

If all of your batteries are 2/3 full before charging, this means that there is 1900 mAh minus 1273 mAh equals 627 mAh of unavailable capacity.

Here's a ballpark formula: total capacity divided by the charging rate = how long it will take (in hours) to fully charge a depleted battery.
In your case 627 mAh divided by 750 mA = 0.836 hour or approximately 50 minutes for the BQ-CC55 to finishing charging 3 or 4 AA batteries.
627 mAh divided by 300 mA = 2.09 hours or about 125 minutes for the BQ-CC17 to finishing charging one or more batteries.

Keep in mind that it takes several charge/discharge cycles for new batteries to be fully broken in where they should easily meet their rated specs.
I don't have an explanation why your results are bass ackwards, maybe you have a half-fast BQ-CC55.

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by ProfJim

You'r welcome.

My BQ-CC17 was used quite a few times while I was gathering test results for my budget charger review. Before charging any batteries, a set of four LSD batteries were fully discharged down to 0.90 volts. My procedure with each charger was to insert all batteries into the charger and then plug the charger into wall outlet. With the BQ-CC17 charger, the green indicator lights would each blink for a one or two seconds and then each indicator would turn solid green.

On one occasion, the battery in the #4 slot started blinking several minutes after all the indicator lights turned solid green. I thought that it might be due to a poor electrical contact, so I gently held the charger with one hand and used my other hand to gently push the #4 battery in and rotate the battery left and right. The indicator light turned solid green and remained solid until the end of the charging session. Using my advanced charger/analyzer to measure each battery's capacity showed that all four batteries were fully charged.

About an hour ago, I put four Fujitsu LSD AA batteries in the BQ-CC17. The indicator lights all turned solid green in less than one second and none of the lights flashed briefly. I measured each battery's voltage with my digital multi-meter before inserting the batteries into the charger. All four batteries had a no load voltage = 1.32 volts. This set of batteries were last charged about six months ago.

Have you tried testing your batteries with your BQ-CC55 charger?
What is the brand and model name of your batteries? How old are the batteries?

Use a tissue paper to clean both battery contact points and do the same for the charger's battery contacts.
Item 3a in the user manual indicates that there is a contact problem.

I assume that your BQ-CC17 is a new unit.
If you don't have a DMM, you can test each battery's voltage using your La Crosse BC900 charger/analyzer.

AFAIK, the CC17 is a new unit. Panasonic sent it to me to test.

The BQ-CC55A charged up my old Gen 1 Sanyo AA and AAA Eneloops without issue. But when I plugged in some of my old AA NiMh batteries, I got the flashing red light of death. The AA NiMh batteries I tried were:1) LaCrosse Tech 2400 mAh2) Energizer 2500 mAh3) Duracell 2650 mAh

The old AAA batteries from Energizer charged without issue on the CC55A. All these batteries are at least 5 years old.

My BC-900 charges the above AA NiMh batteries without issue (other than having to jump start some dead ones with an old Energizer NiMh charger to get the BC-900 to see them). Right now is appears I have to charge my AA Eneloops on one charger and my NiMh batteries on the other.

Since I plan to replace all my existing alkaline and older NiMH batteries with Eneloops as they die out, I should be able to use the CC55A and the CC17 with Eneloops without issue.

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by ProfJim

From my experience, no this is not at all normal.
All of my 1900 mAh LSD AA battery 4-pack kits when new were only about 67% full, give or take 1% or 2% and they all had initial no load voltages ~ 1.32 volts.

When charging four AA batteries, the BQ-CC55 uses a 750 mA charge rate.
The BQ-CC17 always uses a 300 mA charge rate for AA batteries all of the time, whether you're charging one, two, three or four batteries. This means that if all eight batteries have similar initial precharged capacity, the BQ-CC55 batteries should finish much sooner.

If all of your batteries are 2/3 full before charging, this means that there is 1900 mAh minus 1273 mAh equals 627 mAh of unavailable capacity.

Here's a ballpark formula: total capacity divided by the charging rate = how long it will take (in hours) to fully charge a depleted battery.
In your case 627 mAh divided by 750 mA = 0.836 hour or approximately 50 minutes for the BQ-CC55 to finishing charging 3 or 4 AA batteries.
627 mAh divided by 300 mA = 2.09 hours or about 125 minutes for the BQ-CC17 to finishing charging one or more batteries.

Keep in mind that it takes several charge/discharge cycles for new batteries to be fully broken in where they should easily meet their rated specs.
I don't have an explanation why your results are bass ackwards, maybe you have a half-fast BQ-CC55.

Do you have to let the batteries sit in the charger once the lights shut off for a period of time to let it finish the charge? I guess it's called a top off charge.

Re: Eneloops: what charger do I need? (info and discussion thead)

The manual is not that accurate and is a bit misleading. For example the charging process does not start with LED blinking fast several times and then going solid green. My charger goes solid green straight away, there is no blinking-to-solid transition.

Re: Eneloops: what charger do I need? (info and discussion thead)

The manual is not that accurate and is a bit misleading. For example the charging process does not start with LED blinking fast several times and then going solid green. My charger goes solid green straight away, there is no blinking-to-solid transition.

Thank you! I didn't think it would be that different from the CC55 charger, but you never know!

Here is the pertinent info from the BQ-CC55 guide. But I don't see anything about blinking green lights. Combining the info, the CC17 blinking green light must be the same as the CC55 blinking red light.

Re: Eneloops: what charger do I need? (info and discussion thead)

The comments was more towards ProfJim. When he reply that the CC17 is out charging the CC55 is not normal, I was asking if he thinks if there might be a issue with the CC55.

I should of replied with a quote.

If we knew how long it took for each charger to finish charging 4 brand new AA eneloop batteries, we would have pretty conclusive proof as to which charger was under performing. I posted:

Here's a ballpark formula: total capacity divided by the charging rate = how long it will take (in hours) to fully charge a depleted battery.In your case 627 mAh divided by 750 mA = 0.836 hour or approximately 50 minutes for the BQ-CC55 to finishing charging 3 or 4 AA batteries.
627 mAh divided by 300 mA = 2.09 hours or about 125 minutes for the BQ-CC17 to finishing charging one or more batteries.

Panasonic states the following approximate charging times for both chargers when 4 batteries are fully depleted:

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by ProfJim

If we knew how long it took for each charger to finish charging 4 brand new AA eneloop batteries, we would have pretty conclusive proof as to which charger was under performing. I posted:
Panasonic states the following approximate charging times for both chargers when 4 batteries are fully depleted:

BQ-CC17 - 4 AA 1900 - 2000 mAh batteries - 7.0 hours

BQ-CC55 - 4 AA 1900 - 2000 mAh batteries - 3.0 hours

From out of the packaging, into the charger it took about 2.5 to 3 hours til the last light went off. The volt reading was 1.42 to 1.48 when taking off the charger. Some of the battery was finish half hour before the last light went off. I was planning on charging the batteries when the flashlight loses the high mode from battery drain. Then I will pay more attention to the time.

Is there a way to use a digital multi meter to measure the charging amp?

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by carnage

Will the Aneng AN8008 that you just review work measuring this charger?

The general problem with measuring on NiMH chargers it the voltage drop, at 2A the AN8008 will drop about 0.1V, this is significant when measuring on a 1.2V battery, but it is hard to do much better.
Next problem is that most NiMH chargers are pulsing (Check my reviews) and that can make it very difficult to measure anything useful. A max/min function can be useful to capture the maximum current and a average function to show the average charge current.

The AN8008 would measure the current fine enough, but it do not have max/min or average, this makes it a bit hard to get good values.

LiIon chargers are much easier to measure on, the voltage drop in the DMM is less significant and many of them uses steady current.

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by HKJ

The general problem with measuring on NiMH chargers it the voltage drop, at 2A the AN8008 will drop about 0.1V, this is significant when measuring on a 1.2V battery, but it is hard to do much better.
Next problem is that most NiMH chargers are pulsing (Check my reviews) and that can make it very difficult to measure anything useful. A max/min function can be useful to capture the maximum current and a average function to show the average charge current.

The AN8008 would measure the current fine enough, but it do not have max/min or average, this makes it a bit hard to get good values.

LiIon chargers are much easier to measure on, the voltage drop in the DMM is less significant and many of them uses steady current.

I tried a cheap Cen Tech meter someone gave me. I follow the steps in the link you posted and when I tried measuring the charger the meter reading kept on going up and down. I also think the meter can't go into the range I need to be in.

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by carnage

I there any handheld DMM that can read the pulse current or do you need all the fancy equipment HKJ has?

You need a DMM with "average" function. I know it exist on the more fancy handheld DMM's (I have some of them), but I have no idea if any of the cheap DMM's have it (Suggestion for cheap meters to review are welcome, but it can be months before I post a review!).

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by HKJ

You need a DMM with "average" function. I know it exist on the more fancy handheld DMM's (I have some of them), but I have no idea if any of the cheap DMM's have it (Suggestion for cheap meters to review are welcome, but it can be months before I post a review!).

Awhile ago you replied if I want a cheap Fluke my best option was to pick up the Fluke 17B+. Can the 17B+ measure these pulses current?

For a cheap DMM the Cen-Tech 90899 is cheap (people get them for free). Depends on your definition of cheap I would like to see the Uni-t UT139C and the Amprobe 510 there between $35 to $50.

Re: Eneloops: what charger do I need? (info and discussion thead)

@carnage,

It sounds like you need a charger/analyzer to show the charging and/or discharging rates (and other information) for your NiMH batteries while they are in the charger. I've been using the Opus BT-C2000 charger/analyzer for several months; it is excellent and you can buy it for less than $35. You can buy the Opus BT-C2400 unit for a couple of dollars less and the only difference is that the BT-C2400 does not come with the two C & D cell adapters that come with the BT-C2000. Check out HKJ's detailed review: Test/Review of Charger Opus BT-C2000

DC-Workshop is an Opus dealer and you can buy it from them on eBay, Amazon or from their website. they provide technical support and have a one year warranty on units that they sell.

Re: Eneloops: what charger do I need? (info and discussion thead)

Originally Posted by ProfJim

@carnage,

It sounds like you need a charger/analyzer to show the charging and/or discharging rates (and other information) for your NiMH batteries while they are in the charger. I've been using the Opus BT-C2000 charger/analyzer for several months; it is excellent and you can buy it for less than $35. You can buy the Opus BT-C2400 unit for a couple of dollars less and the only difference is that the BT-C2400 does not come with the two C & D cell adapters that come with the BT-C2000. Check out HKJ's detailed review: Test/Review of Charger Opus BT-C2000

DC-Workshop is an Opus dealer and you can buy it from them on eBay, Amazon or from their website. they provide technical support and have a one year warranty on units that they sell.

Eventually I going to pick up a charger/analyzer. I been thinking about the BT-C2000 because of the adapters but not right now.

I just to see if my BQ-CC55 is charging right, being I just bought 2 months ago.